Improvement in the manufacture of white lead



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THOMAS M. FELL ANDjAMBROSE e. FELL. OF BROOKLYN; NEW-YORK, issr-csons TO THEMSELVES ANDWILLIAM BELL, 0 Nit-wrongs: Y. Letters Patent Nopfithl ltl, dated June 25, 1 8 67; dnleddted A i ra n, 1867.

IMPROVEMENT IN THE MANUFACTURE or WHITE so .Stlgthldtt'titttth to in tlgesr gfctlcrs 3mm ant mnhiugoatt iii it: some 'IO'ALL WHOM IT MAY CONCERNS l y Be-it known that we, THOMAS M. FELL and Asinnosu G. FELL, both of the city of Brooklyn. in the State of New York, hove im cnted' certain new and useful improvements in the Manufacture of White-Leadysnd do hereby declare the following to be a' full, clear, and exact description thereof. i

Our present improvements consist in treating the chloridefor oxychloride' of lcad in theunanner hereinafter described, thereby producing a. superior white lead to 'be' uscd osa pigment.

' Chloride of sodiuui when'boilerl or hented undtwell mixed nnd ground with oxide of lead, such oxide being either common lithorge, calcined ores, or other-substancecontaining o. lzirge proportion of oxide,yforms, in the V course of a few hours, a perfect combination producing a chloride oroxychloridc of lead, such. as'is described and claimed by us in a potent bearing even date herewith. j

We find, a's therein stat-ed, thiit twenty per centumof common chloride 'of sodium of a good qu'slityjs about the rightproportion. A considerably greater percentage than this gives. the chloride, after a. further 'lreulmdnt, a dark color, while a much less has a "sirnilarefl'cct. But this lhst-nnmd substance, without 'the vfurther treatment hereinafter mentioned, is not well adopted for the purpose of a pigment, beinglof an impure ,eolor nnd pn-rtiolly soluble by the action of water. -We=consequcntly' convert this chloride or oxychloride of lead into a chlorosulplmtc or white lead, which is pure white in color, possesses a line body, undis insoluble :when mixed as u pigment; To obtain 'this resultwc submit the chloride or oxychloride to an intimate contact with about forty per centum of sulphurie -acid of 60 in lead-lined, gloss, porcelain, or other suitable yessels, arts. temperslturc approaching the boiling point-. This branch of the process requires greot core, and as the sold roduces a powcrfuloud quickaction o the chloride it should he added in small quontities, from time to time, during a period say from two' to, three hours from the commencement, until it is 'all put .in The"nisss then requires digesting' for severnllhours. To enz'ible others to practise our invenl'ion'wc will give the details of its working on alar'gescnle.

We firstdissolve four hundred pounds o'f'the best quality of common suit, as freeos possible from impurities, in sufiicient water. to take up the some, Next, two, thousand pounds ofpxide' 9ilead is well ground sndstirred in' i ldrge vessel 0! mill, 'n-nd mixed with cnougli water to form a'flhin paste; then this pastels boiled or heated to a high rtedlpcroturen The salt solution being also made hot and drained oil from its impurities, is I 'now grnduully odded to the last-numed mixturoiin said ressel, which is lined'with lead, and constructed with a Jmuller .or stirrer so that the material will be WGll lhiXetl or 'ground. Owing to the powerful rind quick'combination the massbecomcs occdsionqlly ery still, which mustbe counteract'edby thorough stirring and grinding, *a'nd by the addition ofsn nll quantitiesxoflwster l'rom time to time. -We usually occupy, in mixing, from. about two to three hours, and then let the moss cool off and digest for from fivef to slx hours,or more, until perfect combination ensues; Instcad'of making it into osolutiori the salt, if known to be pure, can be simply added to the mixture of oxide, nnd'th'e wholc wol l stirred or ground, and so forth, l\ beforestetedgbut'Wve prefer-o solution, as most salt contains more or less impu'rit-ics z I i y r 5 v The contents of thoyessel are now u chloride or oxychloride of lead, and-colour solution'of soda derived from the chloride ofysodiund This solutiou is now drawn qfl as an article of commercq nnd the chloride is lien washed by water until veryrcm'airiing trace of cuustie-soda'is removed; after which it is sguin heated to "the chloride, in order to free it from all traces of acidt then' 'it is dried in the some. manner as practised with" ordinary white lead. Instead of sulphuric acid any salt of that acid, of an equivolent quantity, may be used, "'the result being chlorosulphate of lead and o salt, which salt can be subsequently washed out but the use of '1 Having thus described oiii' new process for'producing white lead, what we claim as new, zsecure by-Letters Potent, is- ,1 l i v i The treatment of chloride of lead in the manner and for'the nurnose substontillly its horeiii d rib d.

moms w. FELL, AMBROSE Gt FELL.

sh d desire to "Witnesses:

' Ammnw J. Tom),

TnoMAsP, PHELAN. 

